U.S. patent application number 12/672288 was filed with the patent office on 2012-04-26 for insulation of a ventilation duct against a wall/ceiling penetration.
This patent application is currently assigned to SAINT-GOBAIN ISOVER. Invention is credited to Leif Andersson, Hans-Jorg Frantz, Horst Keller, Andreas Kohler, Michael Schumm, Torsten Wahls.
Application Number | 20120100319 12/672288 |
Document ID | / |
Family ID | 39832252 |
Filed Date | 2012-04-26 |
United States Patent
Application |
20120100319 |
Kind Code |
A1 |
Keller; Horst ; et
al. |
April 26, 2012 |
INSULATION OF A VENTILATION DUCT AGAINST A WALL/CEILING
PENETRATION
Abstract
The invention concerns the insulation of a duct 2, especially an
air-conditioning or ventilation duct, which passes through a
penetration in a wall 1 or ceiling or the like, and an insulating
material 3 is provided all around the outside of the duct 2. In
this regard, the insulating material 3 has an end face pointing at
least partly in the direction of the penetration. Sections of the
end face, at least, are provided with heat-resistant adhesive
material 11.
Inventors: |
Keller; Horst;
(Wilhelmsfeld, DE) ; Kohler; Andreas; (Mannheim,
DE) ; Wahls; Torsten; (Lubz, DE) ; Andersson;
Leif; (Eslov, SE) ; Frantz; Hans-Jorg;
(Birkenau, DE) ; Schumm; Michael; (Schriesheim,
DE) |
Assignee: |
SAINT-GOBAIN ISOVER
Courbevoie
FR
|
Family ID: |
39832252 |
Appl. No.: |
12/672288 |
Filed: |
August 1, 2008 |
PCT Filed: |
August 1, 2008 |
PCT NO: |
PCT/EP2008/006377 |
371 Date: |
September 12, 2011 |
Current U.S.
Class: |
428/34.5 ;
428/34.1; 428/34.6 |
Current CPC
Class: |
F16L 5/04 20130101; F24F
11/33 20180101; F24F 13/0263 20130101; F16L 59/16 20130101; Y10T
428/13 20150115; Y10T 428/1317 20150115; Y10T 428/1314 20150115;
A62C 2/06 20130101 |
Class at
Publication: |
428/34.5 ;
428/34.1; 428/34.6 |
International
Class: |
B32B 1/08 20060101
B32B001/08 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 8, 2007 |
DE |
10 2007 037 243.6 |
Claims
1. Device for the purpose of insulating a duct (2), especially an
air-conditioning or ventilation duct passing through a penetration
in a wall (1) or ceiling or the like, and a gap between duct (2)
and penetration is filled with packing material (12) and wherein
insulation material (3) is provided around the outside of the duct
(2), and the insulating material (3) makes at least partial contact
with the penetration via its end face, and a heat-resistant
adhesive material (11) is provided over the end face of the
insulating material, preferably over the full surface in some
sections, characterised by the fact that the packing material (12)
at an end pointing to the adhesive material (11) is coated with a
fire-inhibiting foam-forming agent (13) and that the heat-resistant
adhesive material (11) bonds at least part of the surface of the
insulating material (3) to the packing material coated with the
foam-forming agent.
2. Device in accordance with claim 1, characterised by the fact
that the heat-resistant adhesive material (11) bonds at least part
of the surface of the insulating material (3), preferably the full
surface, to angle elements (10 or 10'), especially L-sections,
which, in the vicinity of the penetration, are mounted to the duct
(2) and/or to the wall or ceiling (1) or the like surrounding the
penetration.
3. Device in accordance with claim 1, characterised by the fact
that the heat-resistant adhesive material (11) bonds at least part
of the surface of the insulating material (3), preferably the full
surface, to the wall or ceiling (1).
4. Device for the purpose of insulation in accordance with claim 1,
characterised by the fact that the heat-resistant adhesive material
(11) is a silicate adhesive, especially an adhesive based on
waterglass.
5. Device for the purpose of insulation in accordance with claim 1,
characterised by the fact that the duct (2) is rectangular.
6. Device for the purpose of insulation in accordance with claim 1,
characterised by the fact that the thickness of the insulating
material (3) is greater than the gap (12) and the adhesive material
(11) bonds the insulating material (3) both to the packing material
(12) and to the wall or ceiling (1).
7. Device in accordance with claim 1, characterised by the fact
that the insulating material (3) and the packing material (12) are
formed by mineral wool.
8. Device in accordance with claim 7, characterised by the fact
that the insulating material (3) and the packing material (12) are
formed from rock wool.
9. Device in accordance with claim 7, characterised by the fact
that the insulating material (3) and the packing material (12) are
formed from material wool of the following composition:
TABLE-US-00001 SiO.sub.2 39-55% preferably 40-52% Al.sub.2O.sub.3
16-27% preferably 16-26% CaO 9.5-20% preferably 10-18% MgO 1-5%
preferably 1-4.9% Na.sub.2O 0-15% preferably 2-12% K.sub.2O 0-15%
preferably 2-12% R.sub.2O (Na.sub.2O + K.sub.2O) 10-14.7%
preferably 10-13.5% P.sub.2O.sub.5 0-3% especially .sup. 0-2%
Fe.sub.2O.sub.3 (iron, total) 1.5-15% especially 3.2-8%
B.sub.2O.sub.3 0-2% preferably .sup. 0-1% TiO.sub.2 0-2% preferably
0.4-1% Other 0-2.0%.sup.
wherein especially the composition of the mineral fibres of the
insulating element (4) has an alkali/alkaline earth mass ratio of
<1, and that the fibre structure of the insulating element (4)
is determined by a mean geometrical fibre diameter .ltoreq.4 .mu.m,
a gross density in the range of 20 to 120 kg/m.sup.3 and a binder
content, expressed in terms of the fibre mass of the insulating
element (4), in the range 4 to 7 wt. % in the form of a panel or
0.5 to 1 wt. % in the form of a wire mesh mat.
Description
[0001] The present invention relates to the insulation of a duct,
especially an air-conditioning or ventilation duct, in accordance
with the generic term of claim 1.
[0002] Ventilation ducts are needed in buildings to supply fresh
air to rooms and to connect them, e.g., to a centralized
air-conditioning system. The ducts are passed through penetrations
in the walls and/or ceilings of the rooms. Relevant fire safety
standards stipulate that, in the event of a fire, it or its smoke
may not spread from one building area to another, or if so only
after a delay. For this reason, the wall or ceiling penetration has
to be sealed to prevent the fire from spreading. In this regard, it
must be borne in mind that the fire and its smoke may spread either
through the ventilation duct itself, or through the building gap
between the outside of the duct and the opening of the penetration
in the wall.
[0003] For these reasons, for one thing, the outside of the duct is
sheathed on all sides with a continuous layer of insulation
material, which, for example, is rock wool, to delay an increase in
surface temperature of an insulated section of the duct which is
not affected by fire.
[0004] Furthermore, the wall penetration is sealed. This is done
with packing material, which packs the gap between the wall and the
duct and goes as closely as possible into the insulation material
around the duct. Since this structure is still inadequate for
providing insulation, it is usual to provide a collar of insulation
material which is outside the insulation described above and is in
direct contact with the wall/ceiling. Tests have shown that, while
this collar is good at sealing the wall penetration, the
temperature profile at the duct is influenced in such a way that
elevated temperatures may occur at the transition from the collar
to the described duct insulation. Furthermore, fitting of the
collar entails a costly extra working step.
[0005] The object of the present invention is to insulate a duct in
the area of a wall penetration against temperature increases in a
structurally simple and reliable way such that the conditions of
the relevant fire safety standards are met. At the same time, a
high fire resistance duration is to be achieved and a seal provided
against leakage of gases. Furthermore, the solution is to be
inexpensive and easy to process.
[0006] This object is achieved in accordance with the inventive
characteristics of claim 1.
[0007] According to the invention, a duct, especially an
air-conditioning or ventilation duct, which is passed through a
penetration in a wall or ceiling or the like, is insulated such
that it complies with corresponding fire resistance standards, such
as the provisions of the fire resistance standard DIN 4102-6,
especially L 30 to L 120, depending on the design, that is, a fire
rating of 30 min, 60 min, 90 min, or 120 min. In this connection,
the outside of the duct is wrapped all around with insulation
material that has an end face which points at least partly in the
direction of the penetration and at which a heat-resistant adhesive
material is provided. The insulation material is preferably made of
mineral wool.
[0008] The insulation is needed to hinder or delay a fire, which
has broken out in a first room, from spreading to a second,
adjacent room, there being provided between the two rooms a wall
penetration, through which the aforementioned duct passes.
Similarly, the penetration may be in a ceiling or roof or the like,
but for the sake of simplicity hereafter reference will be
primarily to a wall penetration, which shall also be construed as
including the other types. The fire resistance standards are DIN
4102-6 and the equivalent EN 1366 T1.
[0009] An example of suitable insulating material is mineral wool,
especially a mineral wool of the kind known from EP 1522800 A1. The
use of these insulating materials for the inventive insulating
device is particularly advantageous and is a further inventive
aspect. This wool typically comprises a plurality of thin fibres
made from a heat-resistant material and preferably has a melting
point determined in accordance with DIN 4102 Part 17 of at least
1000.degree. C. However, in addition to these insulation materials,
traditional mineral wools, such as rock wool, or as necessary,
glass wool, are eligible. In general, any material is conceivably
eligible that offers adequate heat resistance and is fibrous.
[0010] Since, in accordance with the invention, the end face, which
points towards the wall penetration, is provided with an adhesive
material, the individual fibres here are bonded. In other words,
the adhesive material is located between the individual fibres at
the end face. Now, if the end face of the insulation material is in
contact with the wall and gases are threatening to come from the
burning room via the wall penetration, i.e. the gap between the
duct and wall into the adjacent room, the increase in density at
the end face that is due to the adhesive material ensures that
ingress into the adjacent room is impeded. The only possibility is
for the gases to force their way into an area between the duct and
the insulation material. However, because this gap, if any, is very
narrow, ingress is hindered for one thing and, for another, it is
of limited harm at this transition area since it still has to pass
through the insulation material before it can reach the adjacent
room. As a result, the ingress of gases can be correspondingly
delayed in time and reduced in quantity, such that corresponding
fire resistance standards are complied with.
[0011] In an advantageous embodiment, the insulation material is
bonded to the wall, as a result of which the end face of the
insulating material is securely connected to the wall. A fire
rating of 60-90 min in accordance with EN1366 T1 requires, for
example, that the insulation material around the duct be up to 90
mm thick. The size of the gap between the wall penetration and the
duct is usually 50 mm on all sides, with this gap width needed
during assembly for the installation of the duct with the attached
connecting elements. The difference between the two is an
overlapping width of 40 mm, in which the insulating material is
bonded to the wall. Penetrating gases are therefore unable to gain
ingress into the adjacent room. The bond is designed to have a high
lifetime even at elevated temperatures.
[0012] When the insulation is being assembled, care is taken to
ensure that the insulating material presses elastically against the
wall on all sides. However, if the insulation material is heated by
hot gases or fire, its property changes and it may soften and
deform. While traditionally this may have created a gap between
wall and insulating material, the bond ensures that the connection
between wall and insulating remains permanent, even at high
temperatures.
[0013] The gap between duct and wall and is usually packed with a
packing material. This packing material affords good insulating
properties at high temperatures, too, and can be the same material
as the insulation material surrounding the duct. The packing
material can comprise one or more strips or panels of insulating
material, which is laid or packed into the gap, or an unstructured,
wool-like substance may be used. Advantageously, the end face of
the insulating material is bonded to this packing material. The
outcome is a continuous sheath of insulating material around the
duct, and the spread of fire and smoke into the room is
hampered.
[0014] The insulation material need not be directly bonded to the
wall, but rather it is also conceivable for further structural
elements, such as profiles, panels, and the like, to which the
insulation material is bonded, to be permanently attached to the
wall.
[0015] The insulating properties of the packing material are
enhanced by advantageously furnishing it with a foam-forming agent.
A foam-forming agent comprises substances which, when heated,
release foam that inhibits the fire and so reduces or delays the
spread of flames.
[0016] Advantageously, the packing material is packed in the
aforementioned gap in a first working step, and then its two end
faces pointing in the direction of the wall are provided with the
foam-forming agent. After the foam-forming agent has
hardened/dried, the packing material, whose surface has thus been
modified, is used for bonding the insulation material here. The
foam-forming agent effectively limits and delays the spread of
fire.
[0017] The aforementioned adhesive material is preferably a
silicate-based adhesive. Such adhesive materials have the advantage
of being easy to process, that is, without much effort--such as by
brushing--onto the insulating material. It is also possible to
first provide the wall or the packing material with the adhesive,
and then to connect it to the insulation material, which is
possibly also provided with adhesive.
[0018] Advantageously, the described insulation is used in ducts
which have an oblong, particularly square cross-section. Since the
duct is surrounded by panels of the insulation material,
appropriately cut-to-size panels can be easily placed on them and
attached to the duct with pins or bolts.
[0019] Profile elements can be attached to the duct in the area of
the penetration. Since, high temperatures occur in a fire, thermal
expansion and stresses also occur on the duct itself, which can
consist of thin sheet metal. As described, the packing material is
located outside the duct in the wall penetration, as a result of
which the duct cannot bulge outwardly. Instead, it might bulge
inwardly at these points. Looking axially at the penetration, this
would produce an extended gap, through which the fire or the gases
could gain ingress. To reduce or avoid these adverse effects, a
profile element, such as an angle shape, may be mounted to the
duct, possibly by riveting. The angle shape could advantageously be
a profile 3 mm+/-1 mm thick, and have flanks 20 mm to 40 mm long.
U-shaped profiles or rectangular shapes are also conceivable.
[0020] Advantageously, one angle shape is attached by one of its
flanks to each side of the duct. The longitudinal direction of the
shapes is in the plane of the wall. Overlapping of the shape to the
wall is achieved by having at least one of the shapes longer than
the size of the wall penetration. Thus, the shape can be mounted to
the wall by, for example, bolts. These mounts enable the duct to be
adjusted relative to the penetration. Thus, the duct is kept stably
in position such that no change in gap width can occur that would
impair the sealing effect across the penetration.
[0021] Preferred embodiments of the present invention are explained
below with the aid of drawings. They show in
[0022] FIG. 1: a ventilation duct with wall penetration in
accordance with the prior art,
[0023] FIG. 2: a view of the duct and wall penetration before
assembly of the insulation material,
[0024] FIG. 3: an inventive insulation, in which the gap between
duct and penetration is smaller than the thickness of the
insulation material and
[0025] FIG. 4: an inventive insulation, in which the gap between
duct and penetration is greater than the thickness of the
insulation material
[0026] FIG. 1 shows the passage of a duct 2 through a wall 1 in the
embodiment of the prior art. The duct is surrounded on all four
sides with insulation material 3. At the transition from insulation
material 3 to the wall 1 is arranged a collar chuck (4), which is
made from insulation material and which seals the wall penetration
against the flames/gases. The collar is attached to the wall 1 with
special nails or dowels (not shown) and presses against the
insulation material 3. The insulation material is predominantly
rock wool. The collar 4 can influence the temperatures at the
measuring points in accordance with EN 1366 Part 1, a fact which
can impact the fire resistance duration.
[0027] FIG. 3 and FIG. 4 show a cross-section through a wall 1 of
two embodiments of the inventive insulation.
[0028] FIG. 3 shows an embodiment with insulation material 3 in a
thickness of 90 mm. For a fire rating of 60-120 min in accordance
with EN 1366 Part 1, a thickness of 30-90 mm is used. The gap
between duct and wall penetration, in which is located the packing
material 12, has a thickness, for example, of 50 mm. If, for
example, the duct is 300 mm high, the height of the wall
penetration is chosen by the client to be 400 mm, such that the
duct, with the mounting elements provided thereon (such as end-face
flange, not shown), can be readily installed. After installation of
the duct, there is an all-round gap of some 50 mm between the duct
and the wall penetration. This gap is traditionally filled with
packing material 12 made from mineral wool, with preference given
to dense packing in order to achieve a good seal against gases and
fire in the event of fire. A layer of fire retardant material,
especially a foam-forming agent 13, is provided at both end faces
of the packing material. Such fire-retardant foam-forming agents
are commercially available. Adjacent these are located angle
profiles 10, which make contact with duct 2 and are attached to it
via rivets 8 (FIG. 2) in the conventional manner.
[0029] As shown in the cross-section of FIG. 3, the insulation
material made from mineral wool 3 sheaths the duct 2. A layer 11 of
adhesive material is provided at the end faces of insulating
material pointing to the wall 1. This layer 11 is divided into
three sections. In an outer section (i.e. away from the centre of
the duct), the insulation material 3 is bonded to the wall 1. In a
central section, the adhesive material 11 bonds the insulating
material 3 to the packing material 12 coated with the foam-forming
agent 13. In an inner section, the insulation material is bonded to
the angle shapes 10.
[0030] In the illustrations of FIGS. 3 and 4, the layers of the
foam-forming agent 13 and adhesive material 11 are shown
disproportionately large for the sake of clarity.
[0031] The insulating effect works as follows: First, a fire is
conceivable in which the fire and/or hot gases spreads out inside
the duct 2. In this case, the insulation material 3 arranged around
the duct 2 works by delaying heat transfer into the interior of the
room. The maximum permissible surface temperature of the insulation
material, as defined in standards, is, for example, 180.degree. C.,
such that its thickness has to be chosen accordingly and also in
relation to the required fire resistance period.
[0032] It is also possible for the fire to spread outside the duct,
i.e. via the gap between the duct and the wall penetration. If it
is assumed that the fire has broken out on the right side of the
wall 1 shown in FIG. 3, it can be assumed that the insulation
material 3, which is located to the right of the wall, is destroyed
relatively quickly. Subsequently, the foam-forming agent 13 shown
on the right side of the wall delays the flames from spreading into
the room shown on the left. Further, fire and smoke must penetrate
through the packing material 12, where it impinges on the second
layer of the film-foam-forming agent 13. To an extent depending on
the intensity of the fire, these means naturally do not constitute
an absolute barrier, but rather serve to produce a desired time
delay in the spread. If the fire has penetrated this second layer
of the foam-forming agent 13, it impinges on the adhesive material
11 provided on insulation material 3, the two main functions of
said adhesive material 11 being as follows: First, the adhesive
material 11 bonds the fibres of the insulation material 13, and
thereby raises the density of the end face of the material. As a
result, penetration of the insulation material by the flames and/or
smoke is impeded. Since the adhesive material 11, as already
described, comprises heat-resistant materials, such as silicate
adhesives, it has a high heat resistance, and so also hinders flame
spread. Furthermore, the adhesive material 11 connects the
insulation material 3 to wall 1. Without this bond, the fire would
carve out a gap and penetrate into the room. Since this possibility
does not exist on account of the bond, the fire can only penetrate
in the area between duct and insulating material. Since the fire,
before it reaches the interior of the room, still has to overcome
the thickness of the insulation material, which in this example is
90 mm, flame spread is effectively hampered, a fact which leads to
wide ranges for the fire rating. Thus, corresponding fire
resistance standards, especially the fire ratings EI 60, EI 90 and
EI 120, can be met simply.
[0033] FIG. 4 shows an alternative embodiment, in which the duct 2
is sheathed with a much thinner layer of the insulation material
3'. This thinner insulating layer 30-35 mm thick is used in
application areas where a fire rating of 15-30 min is required. In
this case, the profile elements 10 are not needed because
deformation of the duct 2 does not exert a significant influence on
the failure of the insulation. As with the case FIG. 3, here,
again, the gap between wall and duct 2 is filled with mineral wool
packing material 12, whose end face is also provided with
corresponding foam-forming agent 13. The insulation material 2 is
bonded to the packing material 12, which is provided with
foam-forming agent, by means of adhesive material 11.
[0034] The application case shown in FIG. 4 resembles that of FIG.
3. However, the end face of insulating material 2 is bonded
exclusively to the packing material 12 coated with foam-forming
agent 13. If, in the event of a fire, the fire overcomes the wall
penetration between the duct 2 and the packing material 12, it
cannot immediately gain ingress to the inside of the adjacent room,
but rather will spread further between the insulation material 3'
and the duct. This will also hamper flame spread accordingly.
[0035] Although not required for the attainment of fire rating EI
15 or EI 3, angle shapes for increasing the rigidity and
facilitating assembly can be provided in the case of embodiments of
FIG. 4.
[0036] FIG. 2 shows the angle shapes 10 and 10' for improving the
dimensional rigidity of the duct. Thus, FIG. 2 shows two angle
shapes 10, which are mounted to the duct 2 by means of three
mounting points 8. Similarly, angles 10' are mounted to the sides
of the duct. Without these angles, the metal of the duct might
twist or bulge inwardly, which would create a gap between packing
material 12 and insulating material 3 to the metal of the duct,
through which the fire and smoke could spread. To avoid this, the
rigidity of the duct in this area is increased by the angles.
Riveting and bolting are ideal means of mounting at the mounting
points 8. Furthermore, the angle shapes 10 are attached to the wall
1 by a wall mounting 7, such as a bolted connection. As a result,
the position of the duct itself relative to the wall penetration is
secured. On the long sides of the duct 2 are shown two profiles 10
and also two further angle shapes 10' at the transverse sides,
which are shorter and not mounted to the wall 1. If the arrangement
in FIG. 2 is sheathed with insulating material 3 and provided with
packing material 12, the result is the embodiment shown in FIG.
3.
[0037] Suitable material for the duct is sheet metal, particularly
sheet steel, which can be galvanized against corrosion. The
thickness should not be less than 0.5 mm or more than 2 mm, with a
thickness between 0.7 and 1.2 mm being advantageous. The
aforementioned angle shape can be a steel profile 3 mm thick, with
a flank length of 20 or 30 mm.
* * * * *